1. Field of the Invention
A helicopter deck preferably for use on offshore oil drilling/production platforms is constructed of modular panels, made of aluminum stringers, which are supported and attached to a preferably polygon circumferential frame made of steel I-beams.
2. Description of the Related Art
Helicopter landing pads which are designed for use on offshore oil drilling/production platforms are usually assembled in place, with the individual structural members and stringers being rigidly and fixedly connected to the drilling platform by nuts and bolts. This results in increased expense in assembly and additional time for assembling the prior art helicopter decks.
A prior art helicopter deck is disclosed in U.S. Pat. No. 5,351,915 which issued on Oct. 4, 1994 and is entitled “Helicopter Deck”. The latter comprises a supporting main frame structure to which is assembled a plurality of elongated deck elements in the form of extruded metal profiles. The extruded metal profiles are individually assembled and connected to the supporting deck and, thus, there is increased cost and assembly time for the helicopter deck disclosed in U.S. Pat. No. 5,351,915.
Reference is also made to other forms of helicopter deck structures which are designed for use in offshore drilling/production platforms and which require the individual assembly of stringers or beams to the supporting structure. As an example, reference is made to U.S. Pat. No. 4,665,857 which issued on May 19, 1987 and is entitled “Landing Pad and Hanger Structure for Vertical Take-Off and Landing Aircraft”. In the latter patent, the individual support structure is first assembled on the deck of the ship, after which individual stringers or beams are secured to the support structure for defining the landing pad.
Other prior art helicopter decks are disclosed in U.S. Pat. No. 4,116,408 which issued on Sep. 26, 1978 and is entitled “Portable Heliport” and U.S. Pat. No. 4,474,130 which issued on Oct. 2, 1984 and is entitled “Helicopter Deck Preferably for Use in Offshore Drilling Production Platforms”.
The prior art also includes new and improved aluminum extrusions of the type disclosed in applicants' U.S. Design Pat. No. 480,157 which issued on Sep. 30, 2002 and U.S. Design Pat. No. 459,491 which issued on Jun. 25, 2002.
The extruded deck beams of U.S. Design Pat. Nos. 480,157 and 459,491 are interconnected at their upper ends by a tongue-and-groove interconnection, with the lower ends thereof being bolted to the support structure so as to form a plurality of modular panels which are secured to a supporting structure.
Each panel includes suitable hatchways which lead to structural supports for enabling the entire helicopter deck to be considered as a unit for fixture to the supporting I-beam structure or the planar support structure.
In the assembly of the prior art helicopter deck, the holes extending through the deck slats and the support structure are individually drilled at the site, thereby resulting in a very time-consuming and expensive assembly and the generation of debris at the site in the form of drilling shavings.
It is an object of the subject invention to provide a new and improved aluminum extrusion of the type used in a helicopter landing deck, as well as a new and improved method of interconnecting the aluminum extrusions to the supporting I-beam structure which facilitates assembly and which minimizes the cost of construction.
It is a further object of the subject invention to provide a modular construction of a helicopter deck, along with the use of new and improved extruded aluminum alloy stringers of the subject invention, so as to provide a light-weight landing pad structure which is readily assembled and cost effective, as well as minimizing on-site production assembly time, and which can be readily disassembled as required in a minimum amount of time.
Furthermore, it is an object of the subject invention to provide a more secure attachment between the modular aluminum extrusions to the supporting I-beam structure or the planar support structure.